JPH03133441A - Irradiating device for laser beam - Google Patents

Abstract

PURPOSE:To prevent the contamination of the tip of an optical fiber, and also, to make the tip part of an irradiating device flexible by joining the transmission body of a laser beam and an optical fiber by an optical joining material which the laser beam can be allowed to transmit through. CONSTITUTION:A probe 1 is constituted of ceramics, etc., and inserted into a blood vessel. A body tube 2 is constituted of plastic of an ethylene tetrafluoride resin, etc., and fitted and connected to the probe 1. On the inside of the body tube 2, for instance, four pieces of optical fibers 4 are provided in parallel on the peripheral of the probe 1 and the center axis of the body tube 2 in a state that its exposed core 4a is adjacent to the back of the back of the probe 1. Each optical fiber 4, 4... is led in from a leading-in hole of a base part of the body tube 2, and held by the probe 1 and the body tube 2 by a joining material 3 in a state that the core 4a is brought into contact to the rear face of the probe 1. At the time of junction by the joining material, the junction can be executed by melting the joining material 3 in advance, and applying the joining material 3 extending over the peripheral of the tip part of the optical fiber 4 and the back of the probe 1 in a state that the tip of the optical fiber 4 is brought into contact with the back of the probe 1.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a laser light irradiation device, for example, a laser light irradiation device that irradiates a laser light onto an animal tissue such as a human body to perform incision, evaporation, thermal treatment, etc. of the tissue. The present invention relates to a laser beam irradiation device used for enlarging narrow passages in living tissue, such as narrowings caused by cholesterol in blood vessels of the human body.

[Conventional technology]

Performing incisions on animals by irradiating laser light is
It has been widely used in recent years because of its excellent hemostatic properties.

In this case, in the past, the laser beam was emitted from the tip of the optical fiber, but due to reasons such as severe damage to the parts, recently it has been changed to transmit the laser beam to the optical fiber and then place it in front of the tip. A laser beam is incident on an emitting probe that may or may not be in contact with human or animal tissue (hereinafter simply referred to as tissue), and while the probe is in contact with the tissue, the laser beam is emitted from the surface of the probe, and the laser beam is emitted from the surface of the probe. The use of a contact probe that irradiates a laser beam is being practiced.

The present inventor has developed various contact (contact type) probes, which are widely used. Using a contact probe has the advantage that as long as the amount of laser light emitted from the probe is adjusted uniformly, the amount of laser light incident on the tissue will always be constant, and the surgeon can easily set the desired irradiation position. Therefore, it is now mainstream.

[Problem to be solved by the invention]

When using such a contact probe, conventionally, the tip of the optical fiber is positioned apart from the back surface (incidence surface) of the probe.

However, if the tip of the optical fiber and the back of the contact probe are separated from each other, the tip of the optical fiber may become contaminated due to, for example, tissue fragments or blood splattered during surgery, and dust in the operating room may enter the separated space. , which can also contaminate the optical fiber tip.

If this contamination occurs, the transmittance of the laser light from the tip of the optical fiber will change, and the laser light generator side should be The output needed to be calibrated in order to prevent rapid surgery. Contamination also causes deterioration of the tip of the optical fiber. moreover,
In order to hold the optical fiber apart from the probe, a connecting fitting is required, and the provision of this connecting fitting prevents the tip of the irradiation device from becoming flexible.

Therefore, an object of the present invention is to eliminate contamination of the tip of an optical fiber and to make the tip of the irradiation device flexible.

[Means to solve the problem]

The above-mentioned problem is provided with a laser beam transmitting body and an optical fiber through which the laser beam is incident on the transmitting body, and an optical bonding material that allows the laser beam to pass through the transmitting body (hereinafter referred to as a probe) and the optical fiber. This can be solved by joining.

Here, it is preferable to use Nd:YAG laser light as the laser light, but other argon laser light or the like may also be used.

On the other hand, if the tip of the optical fiber is brought into contact with the rear surface of the probe, and the periphery of the tip of the optical fiber and the portion of the rear surface of the transmitter excluding the contact surface of the optical fiber tip are bonded using an optical bonding material, the laser beam emitted from the tip of the optical fiber will be The laser beam directly enters the probe, and conversely, the laser beam hardly transmits through the optical bonding material, so that a material with low heat resistance is sufficient as the bonding material.

Providing a plurality of optical fibers for one probe makes it possible to flatten the energy distribution of the laser light emitted from the probe, as will be described later.

A through hole is formed in the center of the probe, and multiple optical fibers are arranged in parallel corresponding to the back of the probe, and a flexible guide wire for inserting the probe is inserted through the through hole. This is effective when inserting a probe into a narrow lumen or blood vessel. In this case, a temperature detection lead for detecting the current tissue temperature can also be inserted through the through hole.

In the case of irradiation with low power, the probe may be made of a plastic material that contains scattering powder that scatters the laser light and is transparent to the laser light.

On the other hand, when a through hole is formed as described above, the laser beam also comes out from the through hole surface, so a reflective layer is formed on the through hole surface so that the laser beam is emitted exclusively from the tip of the probe. It is preferable to make it reflect. This reflective layer can be obtained by gold plating.

Further, as the optical bonding material according to the present invention, a plastic material through which a laser beam can pass can be used, and the probe and the optical fiber tip can be easily bonded while melting the plastic material. The material cost is also cheaper than when connecting metal fittings are used. Furthermore, since metal connecting fittings are not required, all members on the proximal end side of the probe can be made of plastic, making the device as a whole less flexible.

On the other hand, when it is desired to uniformly irradiate the target tissue with laser light from the entire probe, the probe surface has a laser light absorbing powder and a light scattering powder having a higher refractive index than the transmitting body. When a surface layer is formed using a transparent material as a binder, the laser light is scattered in this surface layer.
Uniform irradiation becomes possible.

For the same purpose, a surface layer in which a large number of light-scattering powders do not completely melt and form a uniform layer on the surface of a laser beam transmitter, but instead forms a layer with the powder shape substantially retained, is formed. It can also be formed. In this case, the laser light is irradiated onto the tissue while being repeatedly scattered when it is emitted from the probe surface, when it is incident on the light-scattering powder, and when it is emitted from the light-scattering powder. On the other hand, if the light-scattering powder is completely melted to form a uniform layer, there will be no refraction when the light enters and exits the light-scattering powder, and there will be no scattering effect.

[Effect]

In the present invention, since the probe and the optical fiber tip are bonded using an optical bonding material, the optical fiber tip is not contaminated, calibration for output adjustment is not required, and handling is improved.

In addition, the tip of the optical fiber will not deteriorate, resulting in a longer service life. Furthermore, there is no need for a connecting fitting to hold the probe and the optical fiber tip apart, and instead they are joined using, for example, an optical bonding material made of plastic, making it possible to make the probe tip portion flexible.

[Specific structure of the invention]

The present invention will be explained in more detail below by giving various specific examples.

Figures 1 and 2 show the first embodiment, which is mainly used for angioplasty, where l is a probe made of ceramic or the like, with a rounded part formed around the tip;
This is to reduce the resistance against the inner wall of the blood vessel BV when it is inserted into the blood vessel BV and pushed forward. Reference numeral 2 denotes a main body tube made of a flexible material such as plastic such as tetrafluoroethylene resin, which is fitted and connected to the probe 1.

Inside the main body tube 2, there are a plurality of parallel optical fibers 4, four in the illustrated example, which are optically connected to a laser beam generator (not shown), and their cores 4a are exposed (exposing is not essential). is provided around the central axis of the probe 1 and the main tube 2, with the probe 1 being close to the back surface of the probe 1 (laser light incident surface). Each optical fiber 4, 4...
・ is introduced from the introduction hole 2a at the base of the main body tube 2, and the core 4
A is held in contact with the rear surface of the probe 1 by the bonding material 3 on the probe l and the main body tube 2. When bonding with the bonding material 3, the bonding material 3 is melted in advance,
Bonding can be accomplished by applying the bonding material 3 across the periphery of the tip of the optical fiber 4 and the back surface of the probe 1 with the tip of the optical fiber 4 in contact with the back surface of the probe 1.

On the other hand, a penetrating through hole IA is formed in the center of the probe 1, and this through hole IA communicates with an internal through hole of the bonding material 3. Also, the rear part of the main body pipe 2 is pierced and the conduit 5 is
is provided, and the tip of the conduit 5 is inserted into the bonding material. A flexible guide wire 6 is inserted into the conduit 5, and the guide wire 6 further passes through the inside of the bonding material 3.
It passes through the through hole IA of the probe l and projects forward.

The base side of the guide wire 6 is covered with a plastic coating 7 such as tetrafluoroethylene resin, the distal end is loosely tapered, the tip is spherical, and the entire tip is gold plated 8.
has been done. Reference numeral 9 denotes a thermocouple lead wire that is not used for angioplasty, which is the current target, but is provided for cases such as hyperthermia therapy, and is inserted into the inside of the device.

In the laser beam irradiation device configured in this way, the laser beam from the laser beam generator is transmitted through each optical fiber 4.
The light passes through the probe 1 and reaches its tip, is directly incident on the probe 1 from the tip, travels inside the probe 1, and is emitted from its surface to the target tissue.

In addition, for surgery, first the guide wire 6 is placed outside the body.
penetrate inside the device. Next, the guide wire 6 is inserted into the target blood vessel BV. At that time, the tip of the guide wire 6 is inserted to the front of the stenosis m to be ablated.

Thereafter, the device is inserted into the blood vessel BV using the guide wire 6 as a guide, and the probe 1 is stopped at a position where the front surface of the probe 1 is close to the stenosis m. In this state, a laser beam is introduced into each optical fiber 4, 4..., and the laser beam is emitted from its tip, enters the back of the probe 1, and passes through the inside of the probe 1, mainly from the front of the probe I. A laser beam is emitted and the narrowed portion m is irradiated with the laser beam.

By irradiating the laser beam, the narrowed portion m is cauterized and the inside of the blood vessel is opened. When opening such an opening, as shown in FIG. 4, after cauterization, the balloon 10 may be crushed by air or liquid pressure applied from the outside.

As shown in FIG. 1, in this embodiment, the laser beam is emitted from the periphery of the probe 1, so that the narrowed part m of the inner wall of the blood vessel BV is effectively irradiated, and even with a small laser beam power, it can be cauterized. It is possible.

When the laser beam is irradiated, the protruding portion of the guide wire 6 is irradiated with the laser beam, but since the surface of the tip thereof is coated with gold plating 8, damage is prevented.

In order to avoid irradiation of the laser beam to the center, as shown in FIG. 3, a reflective sleeve 11 made of a thin metal tube is provided on the inner surface of the through hole IA, and a laser beam reflective layer, such as a gold plating layer, is formed on the outer surface of the sleeve 11. By doing so, the laser beam is reflected by the gold plating layer, and the amount of irradiation towards the center of the laser beam is reduced (
can.

In the example shown in FIG. 3, the base side of the optical fiber 4 is held by a holding member 12 made of a suitable plastic material, and the tip part is held by a metal holder 13, and only the tip part of the optical fiber 4 is coated with an optical bonding material. 3. Further, as shown in the figure, the tip of the optical fiber 4 may be connected to the rear surface of the probe 1 at a distance.

In this case, the laser beam emitted from the tip of the optical fiber 4 first enters the bonding material 3, and after passing through the bonding material 3, enters the probe 1.

The optical bonding material according to the present invention is not limited to any material that can transmit laser light, but plastic materials are generally used in terms of bonding or adhesive properties and flexibility. It is preferable to use Examples of this optical bonding material include acrylic resins, polycarbonate resins, polyester resins, epoxy resins, and known ultraviolet curing resins, but ceramic materials,
For example, low melting point glass can also be used.

The apparatus shown in FIGS. 1 and 3 above can also be effectively applied to thermotherapy. That is, as shown in FIG.
A temperature detection conductor 9 having a thermocouple 9a at the tip is inserted into the cancer tissue M through A, and with the probe 1 in contact with the surface of the tissue M, the probe 1 is inserted from each optical fiber 4.4... The tissue M is irradiated with a low amount of laser light through the laser beam.

At that time, the amount of irradiated laser light is controlled so that the tissue temperature is approximately 42 to 44°C.

In this way, the laser beam is directed from the periphery of the probe 1 to the tissue M.
As is clear from the temperature distribution in FIGS. 6 and 7, in the conventional example shown in FIG. Compared to the temperature distribution of laser light, the temperature can be controlled to be uniform over a wide range.

In the example shown in FIG. 5, the through hole IA may not be formed, as may be inferred from the example shown in FIG.
A and a plurality of optical fibers 4 are provided behind the probe 1, a portion of the laser light incident from each optical fiber 4 reaches the through hole IA surface, and a portion of the laser light is refracted and transmitted there. , and the remaining part is reflected and directed toward the tip, so compared to the case without the through hole IA, a larger proportion of the radiation is emitted from the periphery of the front surface of the probe l, resulting in a more uniform temperature distribution. Contribute.

According to the present invention, probes in various forms can be obtained.

For example, the example shown in FIG. 9 can be cited as the simplest one. In this example, an optical fiber 4 is bonded to a probe 20 of an appropriate shape via a bonding material 3. The probe of this example can be used for endoscopy.

If the output of the laser beam emitted from the probe is low,
The amount of laser light incident on the bonding material 3 is extremely small, but when emitted at high output, the amount of laser light incident on the bonding material 3 also increases, causing heat generation and damage to the bonding material 3.

Therefore, for high output, the irradiation apparatus shown in FIGS. 10 and 11 can be suitably used.

In this example, the optical fiber 4 is bonded to the probe 30 using the bonding material 3, and a flexible tube 31 is connected to the rear of the probe 30, and cleaning air or physiological saline W is supplied into the tube 31. Furthermore, notch grooves 3a and 30a are formed in a part of the bonding material 3 and the probe 1, and the supplied physiological saline W is passed through the notch groove 3.
By causing the bonding material 3 to flow out through a and 30a and cooling the bonding material 3 during the flow-out process, damage to the bonding material 3 due to heat generation can be prevented.

On the other hand, in this example, the probe 30 and the optical fiber 4
If there is a possibility that the bonding material 3 may be damaged and separated due to an unexpected external force, for example, as shown in the figure,
A small sleeve 32 made of metal or plastic is inseparably fixed around the tip of the optical fiber 4 by gluing or caulking, and after forming irregularities around the small sleeve 32, the bonding material 3 can be used to bond the small sleeve 32 with the bonding material 3. can. This prevents the optical fiber 4 from being removed from the probe 30.

12 and 13 show a probe 4 without a through hole.
This is an example in which a plurality of optical fibers 4, for example seven optical fibers, are arranged in parallel to each other. 41 is a tube. The principle of laser beam emission in this example is the same as that for each side described above.

Each side above is an example of the structure of a probe used internally, and FIG. 14 shows an example of the structure of a surgical probe. That is, the probe 50 is held by a metal coupling 51, the tip of the optical fiber 4 is held by this coupling 51, and a holder 52 is detachably connected to the coupling 51, so that the tip of the optical fiber 4 and the probe 50 are held together. is optically bonded using bonding material 3.

Further, the bonding material 3 is cooled in the process of supplying the physiological saline W into the holder 52 and causing it to flow out through the through holes 52a and 52b in the holder 52.

On the other hand, the probe is usually made of ceramic material, such as quartz, sapphire, or silica. It is also possible to use a material made of a plastic material that contains scattering powder that scatters the laser beam and that allows laser light to pass therethrough.

As this plastic material, the same material as the above-mentioned bonding material can be used, examples of which include silicone resin,
Acrylic resin (especially methyl methacrylate resin), carbonate resin, polyamide resin, polyethylene resin,
Synthetic resins such as urethane resin or polyester resin,
Particularly preferred are thermoplastic synthetic resins. In addition, since the scattering powder scatters laser light, a material with a higher refractive index for laser light than the above-mentioned plastic material is used, and examples of this include diamond, sapphire, and quartz, whether artificial or natural. system materials,
Single crystal zirconium oxide, translucent heat-resistant plastic (
Examples include powders of composite materials in which the surfaces of these powders are coated with the laser-reflective metals (of course, different types from the above-mentioned plastic materials), laser-reflective metals (such as gold and aluminum), and the surfaces of these powders are coated with the above-mentioned laser-reflective metals. .

If necessary, a laser beam absorbing powder such as carbon, graphite, iron oxide, manganese oxide, etc. may be mixed with the scattering powder, and when the laser beam is emitted while scattering through the probe, the laser beam is mixed with this absorbing powder. It is possible to enhance the heating effect by colliding with and converting it into thermal energy.

The above-mentioned plastic probe can be obtained, for example, by dispersing the above-mentioned scattering powder in a molten plastic material and molding it into a desired shape.

In the laser light irradiation device in this example, the laser light that has entered the probe hits the scattering powder and is repeatedly refracted in the process of being emitted from the outer surface of the probe. Therefore, the light is emitted substantially uniformly from the outer surface of the probe toward the tissue.

In the present invention, a surface layer for enhancing the scattering effect as described below may be formed on the surface of the various probes, as the case may be.

That is, a light scattering powder such as sapphire, silica, or alumina, which has a higher refractive index than the probe material, that is, the ceramic or plastic material, is coated on the surface of the probe.
Furthermore, as mentioned above, it contains laser light absorbing powder such as carbon, which can be mixed into the probe, and forms a surface layer with a binder for film formation.

The light-scattering powder scatters the laser light, and when the laser light is applied to the absorbing powder, most of the energy of the laser light is converted into thermal energy by the light-absorbing powder.

This increases the rate of transpiration of the tissue and allows for easy incision even if the incident energy of the laser beam on the probe is small. Therefore, incision can be made even if the probe is moved at high speed, and surgery can be performed quickly. Furthermore, the ability to reduce the incident power applied to the probe makes it possible to perform surgery with an inexpensive and compact laser beam generator.

On the other hand, when forming the surface layer, even if the above-mentioned absorbing powder and light scattering powder are dispersed in a liquid and applied to the surface of the probe, after the liquid evaporates, both powders physically touch the surface of the probe. Since the probe is simply attached by adsorption force, the surface layer is easily damaged when the probe having the surface layer comes into contact with tissue or hits another object.

Therefore, by providing a binder that binds the absorbent powder and the light scattering powder to the surface of the transmitting member, the adhesion of the surface layer can be improved. In this case, it is preferable to use a light-transmitting powder such as plastic powder or ceramic powder such as quartz as the binder. The film can be formed by melting plastic powder as a binder, or by melting the surface of the probe when using ceramic powder whose melting point is higher than that of the probe.

As another example of a surface layer, a large number of light scattering powders may not completely melt to form a uniform layer, but may form a layered surface layer while substantially retaining the powder shape. . The method for forming this surface layer is to disperse the light-scattering powder in a volatile liquid such as an alcohol, immerse the probe in the liquid, and then remove it from the liquid. A surface layer can be formed by heating the light-scattering powder to a temperature of 100°C to melt a portion of the light-scattering powder, and by this melting, the light-scattering powder is attached to the surface of the probe.

Furthermore, forming irregularities on the surface of the probe or forming the surface layer on the irregular surface is also more effective in uniformly irradiating the laser beam, since the laser light is scattered by the irregularities.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to prevent the tip of the optical fiber from being contaminated and to make it flexible.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a main part of the irradiation device according to the first embodiment of the present invention, FIG. 2 is a view taken along the line ■-■, FIG. The figure is a schematic view of the state in which the irradiation device is inserted into a blood vessel, FIG.
Figure 7 is an explanatory diagram of the temperature distribution, Figure 7 is a plan view of the temperature distribution, Figure 8 is a temperature distribution diagram of the conventional example, Figure 9 is a longitudinal cross-sectional view of a further different example, and Figure 1θ. 11 is a left side view of another embodiment, FIG. 12 is a longitudinal sectional view of another example, FIG. 13 is a left side view of another example, and FIG. 15 is an example of a surgical irradiation device. FIG. 1120.30.40.50...Probe (transparent body)
, IA... Through hole, 3... Optical bonding material, 4 Optical fiber (laser light propagation body), 4a... Core, 6...
Guide wire, 8... Gold plating, 9... Temperature detection conductor, 9a... Thermocouple, IO... Balloon. 11 3 Figure 3 Figure 3 Figure Figure 4α Figure 10 Figure 1 Figure 2 Figure 3 Figure Procedure Amendment (Method) Case Description 1999 Patent Application No. 273539 2゜Invention Relationship to the name of the person who corrects the laser beam irradiation device 3°

Claims (12)

[Claims] (1) It is characterized by comprising a laser beam transmitting body and an optical fiber through which the laser beam is incident on the transmitting body, and the transmitting body and the optical fiber are bonded by an optical bonding material through which the laser beam can pass. Laser light irradiation device. (2) The tip of the optical fiber is brought into contact with the rear surface of the transparent body,
2. The apparatus according to claim 1, wherein the periphery of the tip of the optical fiber and a portion of the rear surface of the transmitter excluding the contact surface of the tip of the optical fiber are bonded by an optical bonding material. (3) A laser beam irradiation device characterized by having a plurality of optical fibers, each of which is arranged in parallel and bonded to a single laser beam transmitting body using an optical bonding material. . (4) The device according to claim 3, wherein the laser light transmitting body has a through hole passing through the center thereof, and a plurality of optical fibers are arranged in parallel corresponding to the rear surface of the transmitting body. (5) The device according to claim 4, wherein a flexible guide wire for inserting the transparent body is inserted through the through hole. (6) The device according to claim 4, wherein a temperature detection conductive wire is inserted through the through hole. (7) The apparatus according to claim 1, wherein the transparent body is made of a plastic material that contains scattering powder that scatters laser light and is transparent to the laser light. (8) The device according to claim 1, wherein the laser light transmitting body has a through hole passing through the center thereof, and a reflective layer is formed on the surface of the through hole. (9) The device according to claim 11, wherein the reflective layer comprises a gold-plated layer. (10) The device according to claim 1, wherein the optical bonding material is made of a plastic material through which laser light can pass. (11) A surface layer is formed on the surface of the laser beam transmitting body, which includes a laser beam absorbing powder and a light scattering powder having a higher refractive index than the transmitting body, and using the laser beam transmitting material as a binder. 2. The apparatus of claim 1. (12) A large number of light-scattering powders do not completely melt to form a uniform layer on the surface of the laser beam transmitter, but instead form a layered surface layer with the powder shape substantially maintained. 2. The apparatus of claim 1.